Use symfony/flex for speed and for limit symfony versions (#318)

Author: Nyholm

.travis.yml

@@ -14,6 +14,7 @@ env:
     - TEST_COMMAND="composer test"
     - SYMFONY_PHPUNIT_VERSION="6.5"
     - COMPOSER_MEMORY_LIMIT=-1
+    - DEPENDENCIES=""
 
 matrix:
     fast_finish: true
@@ -33,10 +34,9 @@ matrix:
 
           # Force some major versions of Symfony
         - php: 7.2
-          env: DEPENDENCIES="dunglas/symfony-lock:^3"
+          env: SYMFONY_VERSION="3.*"
         - php: 7.2
-          env: DEPENDENCIES="dunglas/symfony-lock:^4"
-
+          env: SYMFONY_VERSION="4.*"
 
           # Latest commit to master
         - php: 7.2
@@ -49,11 +49,10 @@ matrix:
 before_install:
     - if [[ $COVERAGE != true ]]; then phpenv config-rm xdebug.ini || true; fi
     - if ! [ -z "$STABILITY" ]; then composer config minimum-stability ${STABILITY}; fi;
-    - if ! [ -z "$DEPENDENCIES" ]; then composer require --no-update ${DEPENDENCIES}; fi;
+    - composer require --no-update symfony/flex ${DEPENDENCIES}
+    - if ! [ -z "$SYMFONY_VERSION" ]; then composer config extra.symfony.require "${SYMFONY_VERSION}"; fi;
 
 install:
-    # To be removed when this issue will be resolved: https://github.com/composer/composer/issues/5355
-    - if [[ "$COMPOSER_FLAGS" == *"--prefer-lowest"* ]]; then composer update --prefer-dist --no-interaction --prefer-stable --quiet; fi
     - composer update ${COMPOSER_FLAGS} --prefer-dist --no-interaction
     - vendor/bin/simple-phpunit install
 
@@ -65,6 +64,3 @@ after_success:
     - if [[ $COVERAGE = true ]]; then wget https://scrutinizer-ci.com/ocular.phar; fi
     - if [[ $COVERAGE = true ]]; then php ocular.phar code-coverage:upload --format=php-clover build/coverage.xml; fi
 
-after_script:
-    - wget http://tnyholm.se/reporter.phar
-    - php reporter.phar build:upload